1. Field of the Invention
The present invention generally relates to a connector case with an improved airtightness consisting of a female connector, to be jointed to a male connector, mounted on a vehicle alternator.
2. Description of the Related Art
Recently, the mounting space for a vehicle alternator becomes more and more limited because of reduction of an engine-mounting space in a vehicle caused by a tendency of slant-nose at a front part of a vehicle for reducing running resistance of a vehicle such as air resistance and needs to enlarge a vehicle compartment space. For such reasons, the vehicle alternator is mounted on a bottom side of the vehicle or piping of a reservoir tank, a brake fluid tank, or a water pump are mounted over or near the vehicle alternator in the vehicle.
When a vehicle alternator is mounted on a bottom side of a vehicle and the vehicle runs on muddy water of a road, the possibility of watering the vehicle alternator from the road is increased. In addition, on mounting various tanks of fluid materials over or near the vehicle alternator, the vehicle alternator is covered with the fluid materials if a supplemental mistake happens during the supplement of the fluid materials to those tanks.
Thus, the mounting environment for the vehicle alternator is deteriorating according to the various needs and demands of the vehicle technologies.
In addition, there is a strong demand to increase the airtightness of connectors mounted on a vehicle, which connect wirings through which control signals are transferred for electrical-communication control in order to perform detailed controls of electric generation of a vehicle alternator, for example, to increase the fuel consumption of an engine, and to reduce the occurrence of engine friction.
In general, a connector mounted on a vehicle alternator is integrated in one body as a part of a resin shield case in a voltage control device (as a voltage regulator). For example, various prior art documents have disclosed such a technique. For example, see on pages 4 to 6, FIG. 1 to FIG. 7 in the Japanese patent laid open publication number JP 2001-16829 where each end part of connector terminals placed in a connector case and exposed to the outside of the connector case is embedded in a resin shield case formed by insert molding and another end part of each connector terminal is exposed as a metal terminal to the outside of the connector case.
By the way, the connector case mounted on a vehicle alternator has a waterproof or moisture-proof capability and is protected by encapsulating rubbers and others placed between an engaging portion between the connector part of the connector case of the vehicle alternator and a connector part for external wirings. However, it is difficult to adhere closely resin with insert-molded terminals in an encapsulating resin case for a voltage regulator placed in the vehicle alternator. For example, even if the resin adheres closely with the insert-molded terminals during a manufacturing process, a crack or a small gap is easily generated between the resin and the insert-molded terminals by heat stress and heat expansion in thermal cycle operation of an internal combustion engine mounted on the vehicle during usual running of the vehicle because of different coefficients of thermal expansion of them and others. When end parts of the metal terminals are exposed to the outside of the encapsulating resin case, through such a crack or a small gap, water or moisture is entered into the inside of the encapsulating resin case, and in the worst case, the water or moisture reaches to the inside of the connector part through the terminal, and the airtightness of the encapsulating resin case is deteriorated.